National health surveys have identified that 30 percent of persons aged 45-64 had some functional limitation or disability, and of those, 50 percent of persons identified that the functional limitations have proven to be the best predictor of mortality, hospitalization, and utilization of health care services included supportive services. However, relatively little attention has been directed to understanding the development of functional limitations (which probably begins for many women in mid-life) and their relation to the development of chronic diseases. We propose to continue and expand a study of physical functioning and osteoarthritis in women age-eligible to experience the menopause, begun as a Michigan site-specific study to the Study of Women Across the Nation (SWAN I), the multi-centered, community-based study of women at the mid-life with a focus on menopause. This study will run concurrently with SWAN II. The goals are to describe the natural history of the development of functional limitations in 500 mid-aged African American and Euro American women. The first goal is to characterize with greater specificity the physical functioning status of mid-aged women using both self-reported and performance-based measures of strength, muscle mass, balance/coordination and joint compromise (radiographically-defined arthritis). The second goal is to determine if the onset (incidence) or severity (progression) of limitations of physical functioning in women (aged 42-52 at baseline of SWAN I) is associated with the menopausal transition. The third goal is to relate measures of physical functioning to markers for chronic diseases including cardiovascular disease, diabetes, hypertension and osteoporosis in a longitudinal manner. There is relatively little research about the natural history of functional limitations among women yet, in the ages of 40-55, there are more women with functional limitations and disabilities than men. Among the elderly, older women live longer, develop more chronic disease and experience more prolonged and severe disability than older men (NCHS, 1997).